This is a rebuild of Drinking Water Watch and not yet the official record. Use the agency’s current Drinking Water Watch for anything you need to rely on.
Chemical and radiological sample results
MS0140010 , Town of Lyon
26 of the 58 analytes this system has been tested for have been detected at least once, across 379 samples on record.
The other 32 were tested for and never found. An analyte is counted here if any result on record measured it, so this covers the whole history and not the samples listed below.
Across all 379 samples on record, detections range from September 28, 1993 to September 30, 2025. These figures cover the whole record.
What counts as a non-detect is defined in the help: Less than Indicator. This system’s violations.
What has been detected, ever
Every analyte measured above its reporting level at any point in this system’s record, most often detected first. This is not limited to the samples listed below.
| Analyte | Kind | Detected in | First detected | Last detected |
|---|---|---|---|---|
| TTHM 2950 | Organic Chemical | 106 of 112 results | Sep 15, 2004 | Sep 24, 2025 |
| Total Haloacetic Acids (Haa5) 2456 | Organic Chemical | 100 of 107 results | Sep 15, 2004 | Sep 24, 2025 |
| Copper, Free 1022 | Inorganic Chemical | 76 of 77 results | Sep 28, 1993 | Sep 30, 2025 |
| Bromodichloromethane 2943 | Organic Chemical | 75 of 79 results | May 16, 2006 | May 19, 2020 |
| Dibromochloromethane 2944 | Organic Chemical | 75 of 79 results | May 16, 2006 | May 19, 2020 |
| Bromoform 2942 | Organic Chemical | 74 of 79 results | May 16, 2006 | May 19, 2020 |
| Dibromoacetic Acid 2454 | Organic Chemical | 72 of 75 results | Oct 11, 2007 | May 19, 2020 |
| Chloroform 2941 | Organic Chemical | 72 of 79 results | May 16, 2006 | May 19, 2020 |
| Trichloroacetic Acid 2452 | Organic Chemical | 66 of 75 results | Oct 11, 2007 | May 19, 2020 |
| Dichloroacetic Acid 2451 | Organic Chemical | 63 of 75 results | Apr 28, 2008 | May 19, 2020 |
| Lead 1030 | Inorganic Chemical | 52 of 77 results | Sep 28, 1993 | Sep 30, 2025 |
| Monobromoacetic Acid 2453 | Organic Chemical | 35 of 75 results | Jan 29, 2008 | Aug 15, 2019 |
| Monochloroacetic Acid 2450 | Organic Chemical | 13 of 75 results | Nov 18, 2009 | May 19, 2020 |
| Arsenic 1005 | Inorganic Chemical | 12 of 12 results | Apr 9, 2002 | Mar 12, 2025 |
| Barium 1010 | Inorganic Chemical | 12 of 12 results | Apr 9, 2002 | Mar 12, 2025 |
| Fluoride 1025 | Inorganic Chemical | 12 of 12 results | Apr 9, 2002 | Mar 12, 2025 |
| Selenium 1045 | Inorganic Chemical | 12 of 12 results | Apr 9, 2002 | Mar 12, 2025 |
| Chromium 1020 | Inorganic Chemical | 8 of 12 results | Apr 9, 2002 | May 11, 2022 |
| Xylenes, Total 2955 | Organic Chemical | 8 of 33 results | Jan 12, 2004 | Apr 20, 2021 |
| Thallium, Total 1085 | Inorganic Chemical | 2 of 12 results | Feb 28, 2005 | Apr 22, 2020 |
| Gross Alpha Particle Activity 4109 | Radionuclide | 2 of 6 results | Sep 28, 2011 | Sep 12, 2012 |
| Nitrite 1041 | Inorganic Chemical | 1 of 20 results | Jan 10, 2022 | Jan 10, 2022 |
| Sodium 1052 | Inorganic Chemical | 1 of 1 result | Sep 25, 2019 | Sep 25, 2019 |
| Gross Alpha, Excl. Radon & U 4000 | Radionuclide | 1 of 2 results | Sep 28, 2011 | Sep 28, 2011 |
| Nickel 1036 | Inorganic Chemical | 1 of 12 results | Mar 24, 2008 | Mar 24, 2008 |
| Mercury 1035 | Inorganic Chemical | 1 of 12 results | Feb 28, 2005 | Feb 28, 2005 |
No date range is applied: this list draws on every sample on record. Show the last two years only.
The most recent samples, result by result
The table below lists 221–230 of 379 samples, newest first — collected August 25, 2011 to March 22, 2012. The summary above covers all 379.
49 results from the 10 samples listed here: 30 detected, 19 not detected. Across the whole record it is 952 of 1,981. A sample is analysed for many analytes at once, so one sample appears on as many rows as it had results.
| Result | Analyte | Monitoring period |
|---|---|---|
|
||
| Not detected below 2.88 pci/l Minimum Reporting Level , sample collected Mar 22, 2012 13:10, sampling point TF101 | Gross Alpha Particle Activity 4109 EPA method 900.0 | Jan 1, 2012 – Mar 31, 2012 |
|
||
| Not detected below 0.002 mg/l Minimum Reporting Level , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Monochloroacetic Acid 2450 EPA method 552.2 | Not recorded |
| 0.004 mg/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Dichloroacetic Acid 2451 EPA method 552.2 | Not recorded |
| 0.003 mg/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Trichloroacetic Acid 2452 EPA method 552.2 | Not recorded |
| Not detected below 0.001 mg/l Minimum Reporting Level , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Monobromoacetic Acid 2453 EPA method 552.2 | Not recorded |
| 0.018 mg/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Dibromoacetic Acid 2454 EPA method 552.2 | Not recorded |
| 0.025 mg/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Total Haloacetic Acids (Haa5) 2456 | Jan 1, 2012 – Mar 31, 2012 |
|
||
| 3.24 ug/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Chloroform 2941 EPA method 524.2 | Not recorded |
| 51.5 ug/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Bromoform 2942 EPA method 524.2 | Not recorded |
| 9.78 ug/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Bromodichloromethane 2943 EPA method 524.2 | Not recorded |
| 36.9 ug/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | Dibromochloromethane 2944 EPA method 524.2 | Not recorded |
| 101.4 ug/l , sample collected Feb 16, 2012 01:15, sampling point MRT000 | TTHM 2950 EPA method 524.2 | Jan 1, 2012 – Mar 31, 2012 |
|
||
| Not detected below 0.1 mg/l Minimum Reporting Level , sample collected Jan 23, 2012 02:00, sampling point TF101 | Nitrate-Nitrite 1038 EPA method 353.2 | Jan 1, 2012 – Dec 31, 2012 |
| Not detected below 0.08 mg/l Minimum Reporting Level , sample collected Jan 23, 2012 02:00, sampling point TF101 | Nitrate 1040 EPA method 353.2 | Jan 1, 2012 – Dec 31, 2012 |
| Not detected below 0.02 mg/l Minimum Reporting Level , sample collected Jan 23, 2012 02:00, sampling point TF101 | Nitrite 1041 EPA method 353.2 | Jan 1, 2012 – Dec 31, 2012 |
|
||
| Not detected below 2.92 pci/l Minimum Reporting Level , sample collected Nov 28, 2011 13:30, sampling point TF101 | Gross Alpha, Excl. Radon & U 4000 | Oct 1, 2011 – Dec 31, 2011 |
| Not detected below 0.067 ug/l Minimum Reporting Level , sample collected Nov 28, 2011 13:30, sampling point TF101 | Combined Uranium 4006 EPA method 200.8 | Oct 1, 2011 – Dec 31, 2011 |
| Not detected below 0.77 pci/l Minimum Reporting Level , sample collected Nov 28, 2011 13:30, sampling point TF101 | Combined Radium (-226 & -228) 4010 | Not recorded |
| Not detected below 0.77 pci/l Minimum Reporting Level , sample collected Nov 28, 2011 13:30, sampling point TF101 | Radium-226 4020 EPA method 903.1 | Oct 1, 2011 – Dec 31, 2011 |
| Not detected below 0.732 pci/l Minimum Reporting Level , sample collected Nov 28, 2011 13:30, sampling point TF101 | Radium-228 4030 EPA method 904.0 | Oct 1, 2011 – Dec 31, 2011 |
| Not detected below 2.92 pci/l Minimum Reporting Level , sample collected Nov 28, 2011 13:30, sampling point TF101 | Gross Alpha Particle Activity 4109 EPA method 900.0 | Oct 1, 2011 – Dec 31, 2011 |
|
||
| 3.81 ug/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Chloroform 2941 EPA method 524.2 | Not recorded |
| 12 ug/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Bromoform 2942 EPA method 524.2 | Not recorded |
| 7.37 ug/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Bromodichloromethane 2943 EPA method 524.2 | Not recorded |
| 18.8 ug/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Dibromochloromethane 2944 EPA method 524.2 | Not recorded |
| 42 ug/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | TTHM 2950 EPA method 524.2 | Oct 1, 2011 – Dec 31, 2011 |
|
||
| Not detected below 0.002 mg/l Minimum Reporting Level , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Monochloroacetic Acid 2450 EPA method 552.2 | Not recorded |
| 0.002 mg/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Dichloroacetic Acid 2451 EPA method 552.2 | Not recorded |
| 0.003 mg/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Trichloroacetic Acid 2452 EPA method 552.2 | Not recorded |
| 0.007 mg/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Monobromoacetic Acid 2453 EPA method 552.2 | Not recorded |
| 0.008 mg/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Dibromoacetic Acid 2454 EPA method 552.2 | Not recorded |
| 0.02 mg/l , sample collected Nov 28, 2011 01:30, sampling point MRT000 | Total Haloacetic Acids (Haa5) 2456 | Oct 1, 2011 – Dec 31, 2011 |
|
||
| 5.51 pci/l The agency recorded which kind of limit this result was below, but stored nothing as the limit itself, which is not a level. The type is published and the value is null. What the limit was is not on record. Whether the result was a detection is a separate column: read resultType. , sample collected Sep 28, 2011 09:30, sampling point TF101 | Gross Alpha, Excl. Radon & U 4000 | Not recorded |
| Not detected below 0.067 ug/l Minimum Reporting Level , sample collected Sep 28, 2011 09:30, sampling point TF101 | Combined Uranium 4006 EPA method 200.8 | Jul 1, 2011 – Sep 30, 2011 |
| Not detected below 0.529 pci/l Minimum Reporting Level , sample collected Sep 28, 2011 09:30, sampling point TF101 | Combined Radium (-226 & -228) 4010 | Not recorded |
| Not detected below 0.478 pci/l Minimum Reporting Level , sample collected Sep 28, 2011 09:30, sampling point TF101 | Radium-226 4020 EPA method 903.1 | Jul 1, 2011 – Sep 30, 2011 |
| Not detected below 0.529 pci/l Minimum Reporting Level , sample collected Sep 28, 2011 09:30, sampling point TF101 | Radium-228 4030 EPA method 904.0 | Jul 1, 2011 – Sep 30, 2011 |
| 5.51 pci/l The agency recorded which kind of limit this result was below, but stored 0.000000000 as the limit itself, which is not a level. The type is published and the value is null. What the limit was is not on record. Whether the result was a detection is a separate column: read resultType. , sample collected Sep 28, 2011 09:30, sampling point TF101 | Gross Alpha Particle Activity 4109 EPA method 900.0 | Jul 1, 2011 – Sep 30, 2011 |
|
||
| Not detected below 0.002 mg/l Minimum Reporting Level , sample collected Aug 25, 2011 01:19, sampling point MRT000 | Monochloroacetic Acid 2450 EPA method 552.2 | Not recorded |
| Not detected below 0.001 mg/l Minimum Reporting Level , sample collected Aug 25, 2011 01:19, sampling point MRT000 | Dichloroacetic Acid 2451 EPA method 552.2 | Not recorded |
| 0.002 mg/l , sample collected Aug 25, 2011 01:19, sampling point MRT000 | Trichloroacetic Acid 2452 EPA method 552.2 | Not recorded |
| 0.004 mg/l , sample collected Aug 25, 2011 01:19, sampling point MRT000 | Monobromoacetic Acid 2453 EPA method 552.2 | Not recorded |
| 0.012 mg/l , sample collected Aug 25, 2011 01:19, sampling point MRT000 | Dibromoacetic Acid 2454 EPA method 552.2 | Not recorded |
| 0.018 mg/l , sample collected Aug 25, 2011 01:19, sampling point MRT000 | Total Haloacetic Acids (Haa5) 2456 | Jul 1, 2011 – Sep 30, 2011 |
|
||
| 2.94 ug/l , sample collected Aug 25, 2011 01:15, sampling point MRT000 | Chloroform 2941 EPA method 524.2 | Not recorded |
| 48 ug/l , sample collected Aug 25, 2011 01:15, sampling point MRT000 | Bromoform 2942 EPA method 524.2 | Not recorded |
| 6.08 ug/l , sample collected Aug 25, 2011 01:15, sampling point MRT000 | Bromodichloromethane 2943 EPA method 524.2 | Not recorded |
| 21.3 ug/l , sample collected Aug 25, 2011 01:15, sampling point MRT000 | Dibromochloromethane 2944 EPA method 524.2 | Not recorded |
| 78 ug/l , sample collected Aug 25, 2011 01:15, sampling point MRT000 | TTHM 2950 EPA method 524.2 | Jul 1, 2011 – Sep 30, 2011 |
-
- Collected
- Mar 22, 2012 13:10
- Sampling point
- TF101 Treatment Plant T101
- Sample type
- Routine
- Lab sample
- 298309001
- Laboratory
- Gel Laboratories
- Monitoring period
- Jan 1, 2012 – Mar 31, 2012
-
Gross Alpha Particle Activity 4109 EPA method 900.0
- Result
- Not detected below 2.88 pci/l Minimum Reporting Level
-
- Collected
- Feb 16, 2012 01:15
- Sampling point
- MRT000 Max. Res. Time
- Sample type
- Routine
- Lab sample
- 120217-012HA
- Laboratory
- MSDH Lab
-
Monochloroacetic Acid 2450 EPA method 552.2
- Result
- Not detected below 0.002 mg/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Dichloroacetic Acid 2451 EPA method 552.2
- Result
- 0.004 mg/l
- Monitoring period
- Not recorded
-
Trichloroacetic Acid 2452 EPA method 552.2
- Result
- 0.003 mg/l
- Monitoring period
- Not recorded
-
Monobromoacetic Acid 2453 EPA method 552.2
- Result
- Not detected below 0.001 mg/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Dibromoacetic Acid 2454 EPA method 552.2
- Result
- 0.018 mg/l
- Monitoring period
- Not recorded
-
Total Haloacetic Acids (Haa5) 2456
- Result
- 0.025 mg/l
- Monitoring period
- Jan 1, 2012 – Mar 31, 2012
-
- Collected
- Feb 16, 2012 01:15
- Sampling point
- MRT000 Max. Res. Time
- Sample type
- Routine
- Lab sample
- 120217-012TH
- Laboratory
- MSDH Lab
-
Chloroform 2941 EPA method 524.2
- Result
- 3.24 ug/l
- Monitoring period
- Not recorded
-
Bromoform 2942 EPA method 524.2
- Result
- 51.5 ug/l
- Monitoring period
- Not recorded
-
Bromodichloromethane 2943 EPA method 524.2
- Result
- 9.78 ug/l
- Monitoring period
- Not recorded
-
Dibromochloromethane 2944 EPA method 524.2
- Result
- 36.9 ug/l
- Monitoring period
- Not recorded
-
TTHM 2950 EPA method 524.2
- Result
- 101.4 ug/l
- Monitoring period
- Jan 1, 2012 – Mar 31, 2012
-
- Collected
- Jan 23, 2012 02:00
- Sampling point
- TF101 Treatment Plant T101
- Sample type
- Routine
- Lab sample
- 120124-071NI
- Laboratory
- MSDH Lab
- Monitoring period
- Jan 1, 2012 – Dec 31, 2012
-
Nitrate-Nitrite 1038 EPA method 353.2
- Result
- Not detected below 0.1 mg/l Minimum Reporting Level
-
Nitrate 1040 EPA method 353.2
- Result
- Not detected below 0.08 mg/l Minimum Reporting Level
-
Nitrite 1041 EPA method 353.2
- Result
- Not detected below 0.02 mg/l Minimum Reporting Level
-
- Collected
- Nov 28, 2011 13:30
- Sampling point
- TF101 Treatment Plant T101
- Sample type
- Routine
- Lab sample
- 291105006
- Laboratory
- Gel Laboratories
-
Gross Alpha, Excl. Radon & U 4000
- Result
- Not detected below 2.92 pci/l Minimum Reporting Level
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
Combined Uranium 4006 EPA method 200.8
- Result
- Not detected below 0.067 ug/l Minimum Reporting Level
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
Combined Radium (-226 & -228) 4010
- Result
- Not detected below 0.77 pci/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Radium-226 4020 EPA method 903.1
- Result
- Not detected below 0.77 pci/l Minimum Reporting Level
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
Radium-228 4030 EPA method 904.0
- Result
- Not detected below 0.732 pci/l Minimum Reporting Level
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
Gross Alpha Particle Activity 4109 EPA method 900.0
- Result
- Not detected below 2.92 pci/l Minimum Reporting Level
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
- Collected
- Nov 28, 2011 01:30
- Sampling point
- MRT000 Max. Res. Time
- Sample type
- Routine
- Lab sample
- 111129-004TH
- Laboratory
- MSDH Lab
-
Chloroform 2941 EPA method 524.2
- Result
- 3.81 ug/l
- Monitoring period
- Not recorded
-
Bromoform 2942 EPA method 524.2
- Result
- 12 ug/l
- Monitoring period
- Not recorded
-
Bromodichloromethane 2943 EPA method 524.2
- Result
- 7.37 ug/l
- Monitoring period
- Not recorded
-
Dibromochloromethane 2944 EPA method 524.2
- Result
- 18.8 ug/l
- Monitoring period
- Not recorded
-
TTHM 2950 EPA method 524.2
- Result
- 42 ug/l
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
- Collected
- Nov 28, 2011 01:30
- Sampling point
- MRT000 Max. Res. Time
- Sample type
- Routine
- Lab sample
- 111129-004HA
- Laboratory
- MSDH Lab
-
Monochloroacetic Acid 2450 EPA method 552.2
- Result
- Not detected below 0.002 mg/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Dichloroacetic Acid 2451 EPA method 552.2
- Result
- 0.002 mg/l
- Monitoring period
- Not recorded
-
Trichloroacetic Acid 2452 EPA method 552.2
- Result
- 0.003 mg/l
- Monitoring period
- Not recorded
-
Monobromoacetic Acid 2453 EPA method 552.2
- Result
- 0.007 mg/l
- Monitoring period
- Not recorded
-
Dibromoacetic Acid 2454 EPA method 552.2
- Result
- 0.008 mg/l
- Monitoring period
- Not recorded
-
Total Haloacetic Acids (Haa5) 2456
- Result
- 0.02 mg/l
- Monitoring period
- Oct 1, 2011 – Dec 31, 2011
-
- Collected
- Sep 28, 2011 09:30
- Sampling point
- TF101 Treatment Plant T101
- Sample type
- Routine
- Lab sample
- 287215024
- Laboratory
- Gel Laboratories
-
Gross Alpha, Excl. Radon & U 4000
- Result
- 5.51 pci/l The agency recorded which kind of limit this result was below, but stored nothing as the limit itself, which is not a level. The type is published and the value is null. What the limit was is not on record. Whether the result was a detection is a separate column: read resultType.
- Monitoring period
- Not recorded
-
Combined Uranium 4006 EPA method 200.8
- Result
- Not detected below 0.067 ug/l Minimum Reporting Level
- Monitoring period
- Jul 1, 2011 – Sep 30, 2011
-
Combined Radium (-226 & -228) 4010
- Result
- Not detected below 0.529 pci/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Radium-226 4020 EPA method 903.1
- Result
- Not detected below 0.478 pci/l Minimum Reporting Level
- Monitoring period
- Jul 1, 2011 – Sep 30, 2011
-
Radium-228 4030 EPA method 904.0
- Result
- Not detected below 0.529 pci/l Minimum Reporting Level
- Monitoring period
- Jul 1, 2011 – Sep 30, 2011
-
Gross Alpha Particle Activity 4109 EPA method 900.0
- Result
- 5.51 pci/l The agency recorded which kind of limit this result was below, but stored 0.000000000 as the limit itself, which is not a level. The type is published and the value is null. What the limit was is not on record. Whether the result was a detection is a separate column: read resultType.
- Monitoring period
- Jul 1, 2011 – Sep 30, 2011
-
- Collected
- Aug 25, 2011 01:19
- Sampling point
- MRT000 Max. Res. Time
- Sample type
- Routine
- Lab sample
- 110826-005HA
- Laboratory
- MSDH Lab
-
Monochloroacetic Acid 2450 EPA method 552.2
- Result
- Not detected below 0.002 mg/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Dichloroacetic Acid 2451 EPA method 552.2
- Result
- Not detected below 0.001 mg/l Minimum Reporting Level
- Monitoring period
- Not recorded
-
Trichloroacetic Acid 2452 EPA method 552.2
- Result
- 0.002 mg/l
- Monitoring period
- Not recorded
-
Monobromoacetic Acid 2453 EPA method 552.2
- Result
- 0.004 mg/l
- Monitoring period
- Not recorded
-
Dibromoacetic Acid 2454 EPA method 552.2
- Result
- 0.012 mg/l
- Monitoring period
- Not recorded
-
Total Haloacetic Acids (Haa5) 2456
- Result
- 0.018 mg/l
- Monitoring period
- Jul 1, 2011 – Sep 30, 2011
-
- Collected
- Aug 25, 2011 01:15
- Sampling point
- MRT000 Max. Res. Time
- Sample type
- Routine
- Lab sample
- 110826-004TH
- Laboratory
- MSDH Lab
-
Chloroform 2941 EPA method 524.2
- Result
- 2.94 ug/l
- Monitoring period
- Not recorded
-
Bromoform 2942 EPA method 524.2
- Result
- 48 ug/l
- Monitoring period
- Not recorded
-
Bromodichloromethane 2943 EPA method 524.2
- Result
- 6.08 ug/l
- Monitoring period
- Not recorded
-
Dibromochloromethane 2944 EPA method 524.2
- Result
- 21.3 ug/l
- Monitoring period
- Not recorded
-
TTHM 2950 EPA method 524.2
- Result
- 78 ug/l
- Monitoring period
- Jul 1, 2011 – Sep 30, 2011
Routine (10).